def f(n):
    for i in range(2, n):
        if n % i == 0:  return False
    return True

cif = ['zero', 'one', 'two', 'three', 'four', 'five', 'six', 'seven', 'eight', 'nine']
left = []
right = []
s = input()
a = s.split()
b = ''
for x in a:
    b+=str(cif.index(x))
b = int(b)
for c in range(2,b):
    if f(c):
        left.append(c)
print(left)
for c in range(b,1015):
    if f(c):
        right.append(c)
print(right)

if b - max(left) <= b - min(right):
    print(max(left))
else:
    print(min(right))